For decades, commuters and tourists have delighted in the mouthwatering smells wafting over the city from the Blommer Chocolate Co. factory.

Now, that aroma is about to disappear, courtesy of federal regulators.

The family-run company, which makes chocolate liquor and cocoa butter among other products, was cited by the U.S. EnvironmentalProtection Agency for violating clean-air regulations and is now installing equipment that will reduce its emissions -- and stop the smell.

"It'll start to go away as we put pollution abatement equipment in place," Vice President Rick Blommer said.

The demise of the rich smell spilling from the cocoa bean processing plant will be a bitter loss for Chicago, said odor researcher Alan Hirsch, head of the Chicago-based Smell & Taste Treatment and Research Foundation.

"Chocolate smells put people in a relaxed state," Hirsch said. "It's been shown bad odors increase aggression; pleasant ones make people more docile. So you could say the chocolate smell is a real service to Chicago."

Smells are a big deal in this city once associated with the stench of slaughtered cows and whose name etymologists say comes from the American Indian words for skunk or onion.

Within smelling range of the 66-year-old factory, it's nearly impossible to find anyone who doesn't rave about the rich, brownie-like aroma.

"I love it," said Maria Negron, 48, as she passed by the factory on her way home from work. "Who wouldn't like the smell of chocolate?"

At least one person in Chicago apparently doesn't.

The EPA said its recent inspection and citation stemmed from a complaint about the plant's smell and emissions. The agency refused to elaborate. Blommer owners also refused to discuss the complaint.

Inhaling the plant's emissions in high concentrations can harm children, the elderly and people with heart and lung diseases, the EPA said.

While environmentalists agree there are some legitimate concerns about the emissions, they also question the EPA's priorities in going after Blommer.

"It's like crushing an ant when there's a pack of wolves around -- then claiming you have saved people from harm," said Brian Urbaszewski of the American Lung Association's Chicago chapter.

Far more pollution is created by power plants, which pump about 15,000 tons of particles into the air annually, Urbaszewski said.

Still, any high concentration of airborne particles, whether from cocoa dust or coal, can irritate respiratory illnesses.

"A lot of people may get a warm, fuzzy feeling from this chocolate smell," he said. "Some people may get the same warm, fuzzy feeling from smelling tobacco -- but that doesn't mean it's good for you."